A NOTE ON GEPHYROCAPSA CARIBBEANICA AND AMPHORA-SHAPED SCYPHOSPHAERA.
Stefan Gartner, Oceanography, Texas A & M Univ., College Station, Tx77843, USA
In INA Newsletter 13/1 Young presented a Quatertnary nannofossil range chart. A couple of points seem inorder so that errors contained in the chart need not be perpetuated. These errors involove 1. the range - indeed
the identi~y - of Gephyrocapsa caribbeanica, and 2. the stratigraphic range of Scyphosphaera spp., more
specifically amphora-shaped Scyphosphaera spp. (e.g. Scyphosphaera amphora, Scyphosphaera pulcherrima).
1. Young indicates an early Pleistocene age for Gephyrocapsa caribbeanica (G. sp. A-B), the youngest

occurrence of the species being at about 1.1 million years. Young follows previous workers, all the way backto Hay et al (1967), who first described the species and designated it the zonal marker for the early Pleistocene,stating that its range extended from " .. the last occurence of Gephyrocapsa oceanica ... ". Unfortunately theproblem surrounding the true identity of Gephyrocapsa caribbeanica starts right there. The stratigraphic rangeof Gephyrocapsa caribbeanica is based on drilled cores - the submarex cores from Nicaragua rise, but theholotype and paratypes are from eleswhere. Hay and Boudreaux, in Hay et al (1967), illustrated four specimens
and designated the stereo pair Plate 12 & 13, Figure 4 the holotype. The holotype and paratype illustrated onPlates 12 & 13, Figure 3, are from the 540cm level of a piston core, A240 Ml. That core was publishedpreviously by Rosholt et al. ( 1961) and the data in that publication indicate a Pleistocene age for the type levelof Gephyrocapsa caribbeanica. More precisely the 540cm level in core A240 M1 is in oxygen isotope stage
8 of Emiliani's numbering system (the same system commonly in use today), and which is also the level of firstoccurrence of Emiliania huxleyi. (Gartner & Emiliani 1976).
[Rosholt et a) (1961) had derived an age of 150ka for this level; then, by matching the classical glacial
stage succession with the generalized (but very limited) Pleistocene palaeotemperature curve known at that timefrom the planktonic foaminifer record, interpreted stage 8 to be the middle of the Mindel/Riss (in North
America the Yarmouth) stage, i.e. early Pleistocene. From there originates the incorrect early Pleistocene age
for Gephyrocapsa caribbeanica.]
The problem, then, is this: Based on objective criteria erelating to the holotype, the earlty Pleistocene"marker" cannot reasonably be Gephyrocapsa caribbeanica; nor can Gephyrocapsa caribbeanica be used as amarker for the early Pleistocene. The two additional paratypes of G. caribbeanica (Plates 12 & 13, Figures
1 & 2) only confirm the problem. These two specimens are from the top of core CG-9, which also yielded thetwo specimens (Plates 12 & 13, Figures 5 & 6) identified as Gephyrocapsa oceanica and the two specimens ofEmiliania huxleyi (Plates 10 & 11, Figures 1 & 2). The species Hey et al (1967) designated Gephyrocapsa
caribbeanica clearly eo-occurs with Gephyrocapsa oceanica and with Emiliania huxleyi and must be late
Pleistocene or, at the very least, extend into the late Pleistocene.
An alternative interpretatioin is that both the holotype and the paratypes of Gephyrocapsa caribbeanica
are redeposited specimens. This interpretation perpetuates instability in nomenclature and in biostratigraphy andis, therefore, not desirable. Perhaps INA could sponsor a further analysis and resolution of this problem.
2. The second point can be made more briefly. it is my experience that the distinctive amphora-shaped
Scyphosphaera (I identify them as Scyphosphaera pulcherrima) are no longer extant. The youngest occurence
seems to be within or near the top of the small Gephyrocapsa interval. Further documentation should render
this species a useful event marker, even though it is often rare. Representative illustrations include PerchNielsen (1985) Figure 52(11) and Figure 53(2).
REFERENCES
Gartner S. & Emiliani C., 1976: Nannofossil biostratigraphy and climatic stages of the Pleistocene Bruhnes epoch. Amer. Assoc. Petrol.
Geol. Bull., 60, 1562-1564.
Hay W.W., Mohler H.P., Roth P.H., Schmidt R.R., & Boudreaux J.E., 1967: Calcareous nannoplanktonzonation of the Cenozoic of theGulf Coast and the Carribean-Antillean area and transoceanic correlation. Trans. Gulf Coast Assoc. geol. Socs., 17, 428-480.
Perch-Nielsen K., 1985: Cenozoic calcareous nannofossils. In Bolli H .M., Saunders J.B. & Perch-Nielsen K., Planlaon Stratigraphy,Cambridge University Press, 427-554.

INA Newsletter 13/3- 1991103

Rosholt J.N., Emiliani C., Geiss J., Koczy F.F., & Wangersky P.J., 1961. Absolute dating of deep-sea cores by the Pa231 rrh 230 method.
J. Geology, 69, 162-185.
Young J.R., 1991: A Quaternary nannofossil range chart. /m. Nannoplankron Ass. News/., 13/1, 14-17.

ORIGINAL AUTHORS REPLY
I am grateful to Gartner for these comments, one of my hopes in publishing the range chart was to stimulate
discussion of this type. Both his points seem entirely valid to me, specifically:
1. This exposition of the true age of the Gephyrocapsa caribbeanica holotype resolves a long standing
uncertainty (Gartner 1977). Manifestly the name G. caribbeanica cannot be applied to the Early Pleistocene
form. Given this G. lumina Bukry 1973 is almost certainly the correct valid alternative. Sorting out the late
Pleistocene taxonomy is a more complex problem- which I skipped over by simply including everything in G.
oceanica. G. caribbeanica has of course priority over G.margereli Breheret (1978) and G. mullerae Breheret(1978). A co-operative effort here might be worthwhile.
2. My use of Scyphosphaera pulcherrima to illustrate the genus Scyphosphaera on the range chart wasobviously unfortunate. Rechecking I find that Gartner's observation of restricted occurrence for this species isin agreement with my data and that of for example Samtleben (1979) and Bergen (1984). I doubt this will everconstitute a useful "marker event" but the occurrence of S. pulcherrima plainly can provide a useful additional
criterion for distinguishing assemblages from above and below the small Gephyrocapsa event.
Jeremy Young, The Natural History Museum, London
REFERENCES
Bergen J.A. 1984: Calcareous nannoplankton from DSDP leg 78A: Evidence for imbricate thrusting at the Lesser Antlilles active margin.
IRDSDP, 78A, 411-447.

Breheret J .G. 1978: Formes nouvelles quaternaires et actuelles de la famille des Gephyrocapsaceae (Coccolithophorides). C. r. Acad. Sci.,

Paris, D287, 447-449.
Bukry D. 1973: Coccolith stratigraphy, East Equatorial Pacific, Leg 16 DSDP. IRDSDP, 16, 653-711.
Gartner S. 1977: Calcareous nannofossil biostratigraphy and revised zonation ofthePleistocene. Mar. Micropalaeom., 2, 1-25.
Samtleben C., 1979: Pliocene to Pleistocene coccolith assemblages from the Sierra Leone Rise, site 366, Leg 41. IRDSDP, 41, 913-931.

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INA Newsletter 13/3- 1991